import math
import sys
def S(): return sys.stdin.readline().rstrip()
def I(): return int(sys.stdin.readline().rstrip())
def MI(): return map(int, sys.stdin.readline().rstrip().split())
def LI(): return list(map(int, sys.stdin.readline().rstrip().split()))
def LS(): return list(sys.stdin.readline().rstrip().split())

a, b = MI()
if a > b:
    a, b = b, a
if a == b:
    print(2**0.5*a)
else:
    print((b**2-a**2)**0.5)